Dual back suction type range hood

ABSTRACT

A dual back suction type range hood includes a wind collecting case. An upper half part and a lower half part of a front surface of the wind collecting case have at least one horizontally extending elongated first air-extracting port and at least one horizontally extending elongated second air-extracting port, respectively. The first air-extracting port is parallel to the second air-extracting port, and the two are in communication with at least one air-extracting device. When the air-extracting device draws air, the total air flow passing through the second air-extracting port is greater than the total air flow passing through the first air-extracting port at a same time. As such, after the second air-extracting port draws most of airborne grease and fumes, the first air-extracting port extracts a very small amount of airborne grease and fumes flowing upwards, thus achieving complete fume exhaustion.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates in general to a dual back suction type range hood, and more particularly, to a dual back suction type range hood that effectively evacuates airborne grease and fumes so as to be applicable in kitchens, factories, and laboratories.

Description of the Related Art

To improve the issue of inadequate exhaust efficiency of a conventional range hood, the Applicant previously developed a range hood with an “air curtain” based on the principles of aerodynamics in the aim of solving the above issue. However, a range hood capable of generating a two-dimensional air curtain requires the simultaneous installation of blowing and venting devices, which can involve extensive complications in replacement and installation and inevitably increase equipment and manpower costs.

In response to the above issue, the Applicant further provided another type of improved range hood that mainly includes a suction hood, a left vertical plate and a right vertical plate. The left and right vertical plates are respectively joined at a lower parts of a left side surface and a right side surface of the suction hood. The suction hood is a housing appearing slightly rectangular, and includes a wind collecting case therein. An elongated exhaust opening is provided at a lower surface of the wind collecting case to extract air upwards.

In practice, the above structure effectively removes airborne grease and fumes. Because the elongated exhaust opening of the structure is located at the lower surface of the wind collecting case, the left and right vertical plates need to have a great length in order to provide separation effects, so that the influence of lateral disturbance air currents can be effectively prevented during the process of extracting airborne grease and fumes through the elongated opening to achieve the expected exhaust performance. However, an overall structure may give a sense of pressure when the left and right vertical plates having a large length are respectively joined at the lower parts of the left and right side surfaces of the suction hood.

SUMMARY OF THE INVENTION

In view of the above issues, the present invention provides a solution that is distinct from the prior art to overcome the issues of the prior art.

It is an object of the present invention to provide a horizontally extending elongated air-extracting port at each of an upper half part and a lower half part of a front surface of a wind collecting case. The total air flow passing through the air-extracting port at the lower half part is greater than the total air flow passing through the air-extracting port at the upper half part of the dual back suction type range hood at a same time. Thus, the issue that an overall structure of a conventional range hood giving a sense pressure is eliminated, and another structure that effectively evacuates airborne grease and fumes is provided while an overall configuration of the range hood is made more simple and appealing.

It is another object of the present invention to provide a dual back suction type range hood. By providing two vertically movable cover plates respectively movably positioned at front surfaces of two elongated air-extracting ports, and a structure of another elongated air-extracting port at the upper cover plate, a user is allowed to select positions for moving the cover plates to be flexibly applicable to fume exhaustion during cooking processes of cooking utensils having different heights.

To achieve the above objects, a dual back suction type range hood of the present invention includes a wind collecting case. The wind collecting case is connected to at least one air-extracting device, and includes a front surface and a back surface opposite the front surface. An upper half part of the front surface of the wind collecting case has at least one horizontally extending elongated first air-extracting port, and a lower half part of the front surface of the wind collecting case has at least one horizontally extending elongated second air-extracting port. The at least one first air-extracting port is parallel to the at least one second air-extracting port. The at least one first air-extracting port and the at least one second air-extracting port are in communication with the at least one air-extracting device. When the at least one air-extracting device draws air, the total air flow passing though the at least one second air-extracting port is greater than the total air flow passing through the at least one first air-extracting port at a same time.

In one embodiment, the wind collecting case has therein an accommodating space, which is in communication with the air-extracting device, the at least one first air-extracting port and the at least one second air-extracting port. The air-extracting device is connected on top of the air collecting case.

In one embodiment, the wind collecting case includes a horizontal upper portion and a vertical portion that are configured as an inverted L-shape.

In one embodiment, the present invention further includes a left vertical plate and a right vertical plate. The left vertical plate is joined at a lower part of a left side surface of the horizontal upper portion, and extends downwards from the lower part of the left side surface. The right vertical plate is joined at a lower part of a right side surface of the horizontal upper portion, and extends downwards from the lower part of the right side surface.

In one embodiment, the lower surface of the horizontal upper portion of the wind collecting case further has at least one extending elongated blowing opening. The at least one blowing opening is located in the front of a front surface of the vertical portion, and is parallel to the at least one first air-extracting port and the at least one second air-extracting port.

In one embodiment, the present invention further includes a second cover plate. The cover plate is movably positioned in a vertically movable manner on a front surface of the at least one second air-extracting port.

In one embodiment, the present invention further includes a first cover plate. The first cover plate is movably positioned on a front surface of the at least one first air-extracting port. A plane of the first cover plate has at least one extending elongated third air-extracting port, which is in communication with the at least one first air-extracting port.

In one embodiment, the present invention further includes a connecting member. Upper and lower ends of the connecting member are respectively connected to the first cover plate and the second cover plate to simultaneously move the first cover plate and the second cover plate.

The above and other aspects of the invention will become better understood with regard to the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective appearance schematic diagram according to a first embodiment of the present invention;

FIG. 2 is a side section schematic diagram according to the first embodiment of the present invention;

FIG. 3 is a front view according to the first embodiment of the present invention;

FIG. 4 is a diagram showing a curve of different pressure losses of a fluid having a same flow passing through different through hole areas;

FIG. 5 is a diagram showing the use according to the first embodiment of the present invention;

FIGS. 6 and 7 are front views of first air-extracting ports in another implementation form according to the first embodiment of the present invention;

FIG. 8 is a perspective appearance schematic diagram according to a second embodiment of the present invention;

FIGS. 9 and 10 are diagrams showing the use according to the second embodiment of the present invention; and

FIG. 11 is a perspective appearance schematic diagram according to a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In a dual back suction type range hood of the present invention, an upper half part and a lower half part of a front surface of a wind collecting case are provided with at least one horizontally extending elongated first air-extracting port and at least one horizontally extending elongated second air-extracting port, respectively. The at least one first air-extracting port is parallel to the at least one second air-extracting port are parallel. The at least one first air-extracting port and the at least one second air-extracting port are in communication with at least one air-extracting device. When the at least one air-extracting device draws air, the total air flow passing through the at least one second air-extracting port is greater than the total air flow passing through the at least one first air-extracting port at a same time. Thus, after the at least one second air-extracting port draws most of airborne grease and fumes, the at least one first air-extracting port completely extracts a very small part of airborne grease and fumes that flow upwards.

Referring to FIGS. 1 to 3, a dual back suction type range hood 1 of the present invention includes a wind collecting case 2 and an air-extracting device 3. In implementation, a left side and a right side of the wind collecting case 2 are defined based on relative positions of a user facing the wind collecting case 2. Further, one side of the wind collecting case 2 close to the user is defined as a front surface, and one side opposite the front surface of the wind collecting case 2 and away from the user is defined as a back surface.

The wind collecting case 2 includes a horizontal upper portion 21 and a vertical portion 22 that are configured as an inverted L-shape. The horizontal upper portion 21 and the vertical portion 22 have therein an accommodating space 23. An upper surface of the horizontal upper portion 21 is provided with an exhaust opening 24, in which a blower serving as the air-extracting device 3 is provided. An upper half part of a front surface of the vertical portion 22 has a plurality of horizontally extending elongated circular holes arranged at an interval. These circular holes serve as first air-extracting ports 221. A lower half part of the front surface of the vertical portion 22 has a horizontally extending elongated, long strip-like hole, which serves as a second air-extracting port 222. The plurality of first air-extracting ports 221 are parallel to the second air-extracting port 222, and the first air-extracting ports 221 and the second air-extracting port 222 are in communication with the air-extracting device 3 via the accommodating space 23 of the air collecting case 2. Further, a lower part of the vertical portion 22 is provided with a grease tank 225, which is in communication with the accommodating space 23 and is for accommodating waste grease.

A though hole area of the second air-extracting port 222 is greater than a total through hole area of the plurality of first air-extracting ports 221. In general, because the exhaust opening 24 of the wind collecting case 22 is located at the upper surface of the horizontal upper portion 21, the plurality of first air-extracting ports 221 are close to the exhaust opening 21 and the second air-extracting port 22 is away from the exhaust opening 24, the total air flow passing through the second air-extracting port 222 is smaller than the total air flow passing through the at least one first air extracting ports 221. However, it should be noted that the through hole area of the second air-extracting port 222 is greater than the total through hole area of the plurality of first air-extracting ports 221. Based on the theory of aerodynamics shown in FIG. 4, when a fluid having a same flow passes through different through hole areas, due to different pressure losses, the total air flow passing through the second air-extracting port 222 is greater than the total air flow passing through the at least one first air-extracting ports 221 at the same time.

Accordingly, as shown in FIG. 5, when a user uses a boiler 9 and airborne grease and fumes are produced, through operations of the air-extracting device 3, the long strip-like second air-extracting port 222 having a large air-extracting amount can draw most of the airborne grease and fumes, and the plurality of first air-extracting ports 221 then completely extract a very small amount of the airborne grease and fumes that flow upwards and discharges the same via the exhaust opening 24.

In implementation, the above first air-extracting ports 221 may be through holes in different geometric shapes such as squares and rectangles, as shown in FIGS. 6 and 7. The second air-extracting port 22 may also be a through hole in different geometric shapes such as a circle, a square or a rectangle. Further, the plurality of second air-extracting ports 222 are in a horizontally arranged at an interval in an elongated manner. The number of the air-extracting device 3 may be two, and the two air-extracting devices 3 are respectively in communication with the at least one first air-extracting port 221 and the at least one second air-extracting port 222. Thus, by controlling different amounts of air extracted, the total air flow passing through the at least one second air-extracting port 222 is greater than the total air flow passing through the at least one first air-extracting port 221 at the same time.

FIGS. 8 to 10 show the dual back suction type range hood 1 according to a second embodiment of the present invention. The second embodiment differs from the first embodiment in that, the second embodiment of the present invention further includes a first cover plate 4, a second cover plate 5 and a connecting member 6. Two sides of the plurality of first air-extracting ports 221 at the front surface of the vertical portion 22 of the wind collecting case 2 are each provided with a first guiding track 223, and two sides of the second air-extracting port 222 are each provided with a second guiding track 224. Thus, the first cover plate 4 can be movably positioned in a vertically movable manner on a front surface of the at least one first air-extracting port 221, and the second cover plate 5 can be movably positioned in a vertically movable manner on a front surface of the at least one second air-extracting port 22.

A plane of the first cover plate 4 has at least one third extending elongated third air-extracting port 41. The third air-extracting port 41 is a through hole in different geometric shapes, such as a circular hole, a square hole or a rectangular hole. When the first cover plate 4 covers the front surface of the at least one first air-extracting port 221, the at least one third air-extracting port 41 is in communication with the at least one first air-extracting port 221, in a way that the total air flow passing through the second air-extracting port 222 is greater than the total air flow passing through the at least one first air-extracting port 221 and the at least one third air-extracting port 41. Upper and lower ends of the connecting member 6 are respectively connected to the first cover plate 4 and the second cover plate 5, so as to simultaneously move the first cover plate 4 and the second cover plate 5.

Thus, when the first cover plate 4 covers the front surface of the at least one first air-extracting port 221 and the second air-extracting port 222 is in an open state, the second air-extracting port 222 draws most of the airborne grease and fumes, and the at least one third air-extracting port 41 completely extracts a very small part of the airborne grease and fumes that flow upwards. When the second cover plate 5 covers the front surface of the second air-extracting port 22 and the at least one first air-extracting port 221 is in an open state, the present invention is applicable during a cooking process of a tall cooking utensil such as a steamer to directly draw the airborne grease and fumes produced by such tall cooking utensil.

FIG. 11 shows a dual back suction type range hood 1 according to a third embodiment of the present invention. Differences of this embodiment from the first embodiment and the second embodiment are that, a lower surface of the horizontal upper portion 21 of the wind collecting case 2 has at least one blowing opening 211. The at least one blowing opening 211 is located in the front of the front surface of the vertical portion 22, and is parallel to the at least one first air-extracting port 211 and the at least one second air-extracting port 222, thereby forming an air current that blows downwards to prevent a possible small amount of airborne grease and fumes from escaping via a lower part of the front surface of the wind collecting case 2. A lower part of a left side surface of the horizontal upper portion 21 is joined with a left vertical plate 212 to have the left vertical plate 212 extend downwards from the lower part of the left side surface. Further, a left arc guiding portion 213 is joined at a right edge of the left vertical plate 212. A lower part of a right side surface of the horizontal upper portion 21 is joined with a right vertical plate 214 to have the right vertical plate 214 extend downwards from the lower part of the right side surface. Further, a right arc guiding portion 215 is joined at a left edge of the right vertical plate 214. Accordingly, blocking effects against air currents at left and right sides of the wind collecting case 2 are generated, and air at a front end and below the wind collecting case 2 can smoothly enter to achieve an air complementing effect. Further, an inverted triangular left upper plate 216 and an inverted triangular right upper plate 217 mutually symmetric are respectively disposed at two sides of a lower surface of the wind collecting case 2. The left upper plate 216 is located between the left arc guiding portion 213 and the exhaust opening 24, and the right upper plate 217 is located between the right arc guiding portion 215 and the exhaust opening 24. More specifically, an upper side of the left upper plate 216 is upwardly adjacent to a left side of the lower surface of the horizontal upper portion 21, and a left side of the left upper plate 216 is leftwardly adjacent to a right side of the left vertical plate 212. An upper side of the right upper plate 217 is upwardly adjacent to a right side of the lower surface of the horizontal upper portion 21, and a right side of the left upper plate 217 is rightwardly adjacent to a left side of the right vertical plate 214. The upper side of the left upper plate 216 and the upper side of the right upper plate 217 are parallel to the blowing opening 211 and are located at a front end of the blowing opening 211, so as to prevent airborne grease and fume contaminants from escaping via intersections of the horizontal upper portion 21 and the left and right vertical plates 212 and 214.

Based on the structure of the first embodiment, assume that an air-extracting channel is 60 cm in length. When the present invention is put to actual tests, a mannequin is placed in front of a cooking station, and two stoves are on the cooking station, with a hot plate used in representation of each of the stoves. The hot plates are heated to 380° C., and sulfur hexafluoride (SF₆) is released on the hot plates. Concentrations of the escaped SF₆ detected at a nose of the mannequin are as follows:

First embodiment of Flow Q_(s) present invention Conventional range hood (m³/min, CMM) Average concentration after 10 minutes C_(ave) (ppm) 10.5 <0.001 17.0 12.0 <0.001 16.9 12.8 <0.001 18.2 13.5 <0.001 19.9 15.0 <0.001 20.5

Thus, the present invention provides following advantages.

First of all, in the present invention, a horizontally extending elongated air-extracting port is provided at each of the upper half part and the lower half part of the front surface of the wind collecting case, and the total air flow passing through the air-extracting port at the lower half part is greater than the total air flow passing through the air-extracting port at the upper half part at the same time. Therefore, the present invention provides a structure that effectively evacuates airborne grease and fumes, and makes the overall configuration of the range hood more simple and appealing.

Secondly, in the present invention, positions for drawing air can be controlled by the two vertically movable cover plates, so as to effectively extract airborne grease and fumes for cooking utensils in different heights, thereby providing application flexibilities.

In conclusion, based on the disclosure of the application, the present invention achieves the expected objects. That is, the dual back suction type range hood of the present invention effectively evacuates airborne grease and fumes, makes the overall configuration more simple and appealing, and can be flexibly applied in cooking processes of cooking utensils in different heights, providing industrial applicability.

While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures. 

What is claimed is:
 1. A dual back suction type range hood, comprising a wind collecting case, the wind collecting case connected to at least one air-extracting device, the wind collecting device having a front surface and a back surface opposite the front surface, an upper half part of the front surface of the wind collecting case having at least one horizontally extending elongated first air-extracting port, a lower half part of the front surface of the wind collecting case having at least one horizontally extending elongated second air-extracting port, the at least one first air-extracting port being parallel to the at least one second air-extracting port, the at least one first air-extracting port and the at least one second air-extracting port being in communication with the at least one air-extracting device; wherein, when the at least one air-extracting device draws air, a total air flow passing through the at least one second air-extracting port is greater than a total air flow passing through the at least one first air-extracting port at a same time.
 2. The dual back suction type range hood according to claim 1, wherein a total through hole area of the at least one second air-extracting port is greater than a total through hole area of the at least one first air-extracting port.
 3. The dual back suction type range hood according to claim 2, wherein the first air-extracting port is a circular hole, and the plurality of first air-extracting ports are horizontally elongated and arranged at an interval.
 4. The dual back suction type range hood according to claim 1, wherein the wind collecting case comprises a horizontal upper portion and a vertical portion that are configured as an inverted L-shaped, and the at least one first air-extracting port and the at least one second air-extracting port are formed on a front surface of the vertical portion.
 5. The dual back suction type range hood according to claim 4, wherein the wind collecting case has therein an accommodating space, the accommodating space is in communication with the air-extracting device, the at least one first air-extracting port and the at least one second air-extracting port, and the air-extracting device is connected on top of the wind collecting case.
 6. The dual back suction type range hood according to claim 4, further comprising a left vertical plate and a right vertical plate, the left vertical plate is joined at a lower part of a left side surface of the horizontal upper portion and extends downwards from the lower part of left side surface, and the right vertical plate is joined at a lower part of right side surface of the horizontal upper portion and extends downwards from the lower part of the right side surface.
 7. The dual back suction type range hood according to claim 4, wherein a lower surface of the horizontal upper portion of the wind collecting case further has a least one blowing opening, and the at least one blowing opening is located in the front of the front surface of the vertical portion and is parallel to the at least one first air-extracting port and the at least one second air-extracting port.
 8. The dual back suction type range hood according to claim 1, further comprising a second cover plate, and the second cover plate is movably positioned in a vertically movable manner on a front surface of the at least one second air-extracting port.
 9. The dual back suction type range hood according to claim 8, further comprising a first cover plate, the first cover plate is movably positioned in a vertically movable manner on a front surface of the at least one first air-extracting port, a plane of the first cover plate has at least one extending elongated third air-extracting port, and the at least one third air-extracting port is in communication with the at least one first air-extracting port.
 10. The dual back suction type range hood according to claim 9, further comprising a connecting member, and upper and lower ends of the connecting member are respectively connected to the first cover plate and the second cover plate to simultaneously move the first upper plate and the second upper plate. 